Sewing machine



C. F. RUBEL SEWING MACHINE Feb. 9, 1943.

Filed March 26, 19.40 3 Sheets-Sheet 1 Feb. 9,' C. F. RUBEL 7 SEWING MACHINE Filed March 26, 1940 s Sheets-Sheet 2 W1 TNESSES: R INVENTOR:

' Charles ii ifubel,

3 Sheets-Shee? I:

C. F. RUBEL SEWING MACHINE Filed March 26, 1940 Feb. 9, 1943.

INVENTOR:

Charles i'RubeL,

, l IIIIIIIIIII W1 TNESSES:

A T'IORNEYS.

Patented Feb. 9, 1943 UNETE rem orrlce SEWING MACHINE Charles F. Rube], Chicago, Ill., assignor to Union Special Machine Company, Chicago, Ill., a corporation of Illinois 6 Claims.

This invention relates to sewing machines, and has reference more especially to multiple needle chain stitch sewing machines of the type disclosed in U. S. Patent 1,444,634 granted to J. R. Mofiatt on February 6, 1923, wherein a gang of of spreaders laterally drawthe threads from an associated gang of thread carrying loopers to form loops from such threads for entry of a corresponding gang of needles as the latter descend. Machines of the kind referred to are designed for the seaming of relatively heavy fabrics which are difficult to penetrate with the result that the needles very often flex and bend in the direction of the seam, and/or laterally of the line of the seam under the strain imposed upon them with attendant malformation of stitches and/or fouling of the loopers.

The aim of my invention is to preclude such contingencies, which objective I attain in practice as hereinafter more fully disclosed, through provision of a guard means which is simple in construction and which is mounted on the support carrying the spreaders so as to move in synchronism with the latter, and which, when the spreaders are at the end of their loop spreading shift, present beveled surfaces for engaging the needles in the event that they are flexed either in the direction of the line of the seam being formed, or laterally toward the loopers under the conditions above mentioned.

Other objects and corresponding advantages of my invention will appear from the following detailed description of the attached drawings, wherein Fig. 1 is a fragmentary view, partly in front elevation and partly in vertical longitudinal section, of a sewing machine conveniently embodying my invention.

Fig. 2 is a fragmentary view of the machine in plan with its work supporting plate removed to expose underlying parts which would otherwise be hidden.

Fig. 3 is a cross section of the machine looking The sewing machine herein illustrated for the purposes of exemplifying my invention is generally of the construction set forth in the patent above referred to, having a base In with upstanding crosswise pedestal webs H and 52 at intervals of its length whereon is mounted a work supporting plate I3. overhanging the work support is a frame arm 55 with a head 16 which provides spaced upper and lower guide bearings I! and I8 for an upright needle bar 19. Through a short link connection at 20 with a vibrating lever 2|, the needle bar I9 is vertically reciprocated in a Well known manner. At the lower end of the needle bar I!) is a cross head or gang bar 22 which carries two groups of needles 23 and 24 spaced transversely of the plane of feeding, which latter takes place away from the observer in Fig. 1 and in the direction indicated by the large straight arrows in Figs. 3 and 4. The presser foot 25 of the machine is apertured as shown in Fig. 1 for passage of the needles 23, 24 through it, and is secured to the lower end of a presser bar 26, which, like the needle bar is is guided for up and down movement in suitable bearings on the head 16. The presser bar 26 is subject to the action of a spring (not illustrated), whereby the presser foot 25 is yieldingly maintained in contact with the fabric F (Fig. 4) being seamed in the machine. Extending lengthwise of the base I beneath the work support I3 is a drive shaft 21 which is suitably journalled in the pedestals H and I2. Mounted on the drive shaft 21 is an eccentric cam 28 whereon rests a feed bar 29 with a separately attached underreaching portion 3%! in engagement with bottom of said cam. At the top of its forward end, the feed bar 29 has a transverse groove 3| wherein is engaged the pendant tongue 32 of the cross head 33 having a longitudinal slot 34 and an upstanding longitudinal ridge 35 centralized with respect to said slot. The cross head 33 is held against displacement on the feed bar 29 by a clamp member 36. Mounted in turn on the cross head 33 are three feed dog sections 38, 39 and 49. As instanced in Fig. 3, each feed dog section has a transverse groove M in the bottom of its shank to engage over the ridge 35 of the cross bar 33, and is secured in position by a screw 42 whereof the shank passes down through the slot of said bar and threadedly engages a clamp piece 43. The forwardly-extending ends of the feed dog sections 38-69 are bifurcated (see Fig. 2) to clear the needles, and provided at their tops with upstanding fabric engaging teeth. The construction just described, enables adjustment of the feed dog sections not only relative to each other, but also laterally as a group or gang relative to the needles. Set into the work support I3 is a throat plate 45, which, as shown in Fig. 1, is appropriately slotted for protrusion through it of the toothed portions of the feed dog sections 30-40. At its rear end, the feed bar 29 is pivotally connected by a pin 45 to the top of a vertical rocker 41 mounted for oscillation on a fulcrum pin 43 whereof the ends are engaged in spaced bearing lug projections 49 and 50 at the rear of the base Ill. Secured to the feed rocker 41 is a forwardly extending arm 5|, which, see Fig. 2, is pivotally connected at 52 to the strap 53 of another rotary actuator 55 on the drive shaft 2'! immediately inward of the pedestal II. As a consequence of these connections, fabric advancing movements are induced in the feed dog sections 38-40, lift movements being imparted to the latter by the rotary actuator 28.

Arranged to cooperate with the needles 23 and 24 below the work support I3 in stitch formation, are corresponding groups of thread-carrying loopers 55 and 57, the shanks of which loopers are secured in separate holders 58 and 59. As instanced in Fig. 4, each such holder is in the form of a block with a crosswise ridge 60 at the back thereof engaging into the longitudinal slot in the wing 62 of a carrying member 63, which, see Fig. 2, has bosses 65 and 60 at its opposite ends surrounding a shaft 61 whereto said member is fixed by a set screw 68 passing through one of the bosses. Each looper holder block is fixed in position by a retaining piece 69 at the back of the wing 02 of the member 03 having a tongue extending into the slot BI and being secured by a clamp screw 70. Here again, as is the case with the feed dog sections 38-40, the looper groups 56 and 51 are laterally adjustable with respect to each other and also as a group or gang relative to the needles 23, 24. As shown in Fig. 2, the looper shaft 51 is parallel with the drive shaft 21 and located forwardly thereof, and likewise journalled in the pedestals II and I2. Clamped on the left hand end of the looper shaft 6'! is a pendant arm II which has a ball connection I2 with one end of a pitman E3, the other end of the pitrnan being similarly connected at I4 with a crank I on the corresponding end of the drive shaft 2?. As a consequence of this arrangement, the looper shaft 61 is oscillated to impart loop taking movements to the loopers 56 and 51, The means for imparting endwise movements to the looper shaft 01, and, in turn, needle avoiding movements to the loopers, includes a third rotary actuator on the drive shaft 21 having the form of an eccentric TI, which, as shown in Fig. 2, is located rightward of the pedestal I2. The strap rod I8 of the eccentric is connected with a ball 79 at the end of one arm 00 of a rocker 8I which oscillates about a stud 82 upstanding from the base I0, another arm 83 of said rocker being connected, through the medium of short link 85, with the rear end of the looper shaft 61-. Disposed forwardly of the looper shaft 01 at a slightly higher level is an endwise shiftable horizontal rod 80 which is supported at its opposite ends by upright guide brackets 81 and 88 secured to the front of the machine base I0. Rotation of the rod 85 is prevented through sliding engagement of a pendant arm 80 thereon with a lateral stud projection 00 on the bracket 01. The rod 80 receives its endwise movements by virtue of a pitman connection 9| with still another arm 92 on the rocker 8|, which arm is directly opposite the other arm 33 of said rocker. Accordingly the looper shaft 61 and the rod 86 are shifted contrariwise in their endwise reciprocations. Affixed to the rod by set screws 93 is a carrier bracket 55 with fiat longitudinal top surface whereon is mounted a pair of spreaders 3E and 91 which respectively cooperate with the loopers 55, 51 in laterally distending the looper thread into loops for entry hereinto of the needles 23, 24. These spreaders 95 and 91 have the form of tongues which extend inwardly (in the direction of feeding) toward the needle 23, 24, immediately above the path of the loopers 5G, 51, and which, at the undersides of their free ends, are recessed as at 98 and 99 to engage the looper threads substantially in the same manner as disclosed in U. S. Patent #1,995,078 granted to C. F. Rubel on March 19, 1935.

However, instead of being in one, as in the patent just referred to, the spreaders 96, Bl of my machine are separately formed so that they may be independently adjusted laterally relative to the looper groups 55 and 51 with which they respectively cooperate. In order to make such adjustment possible, the anchorage portions 96a, 07a of the spreaders 95, 91 are transversely slotted (see Fig. 2) for passage of the shanks of the cap screws I00, I 0| by which they are secured to the bracket 95.

For the purpose of bracing the needles 23, 24 to prevent them from fouling the loopers in the event that they are flexed in passing through the fabric, I have, in accordance with my invention, provided a guard I02, which, as shown in Figs. 1, 5 and 6, has the configuration of the letter T with its shank I03 secured to the top of the bracket 05 in the interval between the spreaders 05, 91, and its cross bar I04 extending crosswise of the front of the needles 23, 24 at a level immediately below the path of the loopers. From Figs. 4 and 5, it will be observed that the cross bar I04 of the guard I52 is of triangular cross section with the taper in the direction of the needles, and that it is provided in its longitudinal front edge with angular needle-receiving notches I05, I00 the two sides of which are beveled as at I01 for camming action with one of the needles. The notches I05, I06 are relatively wide so as to allow for the endwise shifting of the guard IE2, and as shown in Fig, 5, the shank I03 of said guard is longitudinally slotted for passage of the shank of the screw I08 by which it is secured to the bracket 95. As a consequence, the guard I 02 can be adjusted in the direction of feeding relative to the needles 23, 24.

During each stitch forming cycle of the machine, the spreaders 96 and 91 are moved rightward in Figs. 1 and 2, and by reason of being affixed to the same support, the guard I02 is concurrently moved with said spreaders to the limit position in which it is illustrated in Fig. 6 in respect to the needles 23 and 24. Thus normally the needles 23 and 24 will pass down through the notches I05, I00 of the guard I02 without engaging either of the beveled edges ID! of said notches. However, in the event that, on its downward stroke through the material being seamed, a needle 23 or 24 is deflected or bent rightward in Fig. 6 in the direction of the seam, it will be engaged by the inner beveled edge of the corresponding notch I05 or I06, as the case may be, and thus properly positioned in the line of the seam. On the other hand, if on its down stroke. a needle 23 or 24 should be deflected or bent laterally toward the respectively associated looper 56 or 51, it will be engaged by the beveled side edge of th corresponding notch of the guard I02 and be thereby properly positioned relative to such looper and accordingly prevented from fouling the latter. From the foregoing it will be apparent that I have provided a simple and positive means for preventing the malformation of stitches, and at the same time precluding damage to the loopers if the needles should be accidentally deflected from their normal line or up and down travel.

It is to be understood that my invention is not to be regarded as restricted to the precise number or arrangement of needles, loopers and spreaders herein shown and described by way of example.

Having thus described my invention, I claim:

1. A sewing machine comprising a plurality of needles which are spaced laterally of the direction of feeding; respectively associated threadcarrying loopers; means for imparting back and forth needle loop engaging movements to the loopers in the direction of feeding; spreaders confied to back and forth movement en masse crosswise of the direction of feeding to laterally draw the threads of the respective loopers into loops for entry of the associated needles; a needle guard common to the needles and connected for movement in unison with the spreaders and having notches open in the direction of feeding, said notches being Wider than the needles to allow for the movement of the spreaders and respectively providing camming surfaces at an angle to each other for engaging and directing the corresponding needles in the event that they are bent or flexed, to insure proper cooperation of said needles with the loopers.

2. A sewing machine comprising in combination, a plurality of needles spaced laterally of the direction of feeding; a work support through which the needles pass; a plurality of thread carrying loopers below the work support; means for imparting back and forth needle engaging movements to the loopers in the direction of feeding; spreaders in a plane immediately above the paths of the loopers to laterally draw the looper threads into loops for entry thereinto of the respective needles; a needle guard common to the needles lying in a plane immediately below the path of the loopers and connected for movement in unison with the spreaders and having notches corresponding in number to the needles and open in the direction of feeding, said notches being wider than the needles to allow for the movement of the spreaders and providing camming surfaces at an angle to each other for respectively engaging and directing the needles in the event that they are bent or flexed, to insure proper cooperation of said needles with the loopers.

3. A sewing machine comprising in combination, a thread carrying needle; a thread carrying looper; means for imparting loop taking and needle avoiding movements to the looper; a spreader; means for moving the spreader backward and forward laterally of the looper to draw the looper thread into a loop for entry of the needle; and

a needle guard connected to the spreader for movement in unison therewith, and having a needle receiving notch which is open in the direction of feeding, said notch being wider than the needle to allow for the movement of the spreader, and providing camming surfaces at an angle to each other for engaging and directing the needle in the event that it is bent or flexed, to insure proper cooperation of said needle with the looper.

4. A sewing machine comprising, in combination, a reciprocative thread carrying needle; a thread carrying looper; means for imparting loop taking and needle avoiding movements to the looper; a movable guard with a camming surface which is adapted, in the event that on its down stroke the needle is deflected or bent in the direction of the seam being formed in the machine, to engage the needle and correctly position it in the line of the seam, and another camming surface which is adapted to engage the needle in the event that on its down stroke it is bent or deflected transversely of the line of the seam and thereby position it correctly with respect to the looper as the latter advances to engage the needle thread; and means for actuating the guard to operate in the manner set forth.

5. A sewing machine comprising, in combination, a reciprocative thread carrying needle; a

thread carrying looper; means for imparting loop taking and needle avoiding movements to the looper; a movable guard with an angular notch whereof one side constitutes a camming surface which is adapted, in the event that on its down stroke the needle is deflected or bent in the direction of the seam being formed in the machine, to engage the needle and to correctly position it longitudinally of the line of the seam, and the other side of said notch constituting another camming surface which is adapted to engage the needle in the event that on its down stroke it is bent or deflected transversely of the line of the seam, thereby to position the needle properly with respect to the looper as the latter advances to engage the needle thread; and means for actuating the guard to operate in the manner set forth.

6. A sewing machine comprising, in combination, plural laterally spaced reciprocative thread carrying needles; plural thread carrying loopers to cooperate individually with said needles; means for imparting loop taking and needle avoiding movements to the several loopers; a movable guard with a pair of camming surfaces for each needle, one such surface adapted, in the event that on its down stroke the needle is deflected or-bent in the direction of the seam being formed in the machine, to engage the needle and correctly position it longitudinally of the line of the seam, and the other camming surface adapted to engage the needle in the event that on its down stroke it is deflected or bent transversely of the line of the seam and thereby to position the needle correctly with respect to the corresponding looper as the latter advances to engage the needle thread; and means for actuating the guard to operate in the manner set forth.

CHARLES F. RUBEL. 

